MBE Growth Study of GaAsSbN/GaAs Single Quantum Wells
- PDF / 83,301 Bytes
- 7 Pages / 612 x 792 pts (letter) Page_size
- 33 Downloads / 253 Views
Z1.9.1
MBE Growth Study of GaAsSbN/GaAs Single Quantum Wells Liangjin Wu, Shanthi Iyer, Kalyan Nunna, Jia Li, Sudhakar Bharatan, and Ward Collis, Department of Electrical & Computer Engineering North Carolina A&T State University Greensboro, NC 27411 Kevin Matney, Bede Scientific Inc, Englewood, CO Abstract In this work, the growth and properties of GaAsSbN single quantum wells are investigated. The heterostructures were grown on GaAs substrates in an elemental solid source molecular beam epitaxy system with a RF plasma nitrogen source. A systematic study has been carried out to determine the influence of growth temperature on the optical properties of the layers. For reference low temperature photoluminescence (PL) characteristics of the GaAsSb/GaAs QWs as a function of Sb is also presented. A significant increase in PL intensity with a corresponding blue shift in emission energy and a decrease in full width at half maximum (FWHM) has been observed on annealing the GaAsSbN/GaAs sample in a nitrogen ambient at 700˚C. PL emission wavelength as long as 1.52 µm at room temperature has been obtained on annealed samples.
I. Introduction The dilute nitride alloy systems lattice matched to GaAs are currently being extensively investigated as an alternative to InP and GaSb based systems for optoelectronic device applications in the laser based radar and optical communication systems. Amongst the different nitrides, namely InGaAsN, GaInAsSbN and GaAsSbN, the InGaAsN material system is the most extensively studied system. In spite of the rapid progress, there are still some serious problems associated with this alloy system, particularly the difficulty in achieving emission at wavelengths larger than 1.5 µm [1, 2]. Recently the InGaAsSbN system has been demonstrated to overcome this problem using the surfactant properties of Sb and lasers with emission wavelengths as long as 1.49 µm have been fabricated [3]. However, the presence of five components makes the growth complex. Hence, the GaAsSbN alloy still remains attractive due to one lower constituent element and further, longer wavelength can be achieved in comparison to the InGaAsN system due to the smaller strain in the corresponding ternary GaAsSb material for similar N composition.
Z1.9.2
The work on this system has been carried out primarily by Ungaro et al. [4] and Harmand et al.[5, 6]. N incorporation (as much as 2.5%) has been successfully accomplished in this material system by Harmand et al. [5] using molecular beam epitaxial (MBE) technique. Jones et al. [7] have also published similar results on the growth of this alloy system. This work is our preliminary report on the effect of the growth temperature on the low temperature PL and limited x-ray characteristics on both as grown and annealed samples of GaAsSbN/GaAs quantum wells grown by MBE technique.
II. Experimental Details The GaAsSbN QW samples were grown on semi-insulating GaAs (100) substrate in an EPI 930 solid source MBE system using elemental Ga with thermally cracked As and Sb sources. The active
Data Loading...
